Everyone who has lived in a house located in a climatic zone which includes periods of freezing weather has had to be concerned about the possibility of water pipes freezing and bursting. Measures commonly used to prevent the freezing of water pipes include insulation of all pipes, running water continuously through the exposed pipe, and heating the pipe. None of these measures is entirely satisfactory and it has long been an engineering hope to provide a simple inexpensive pipe that would, in temperate climate zones, be able to withstand temperatures down to about 0.degree. F. without permitting the pipe to burst due to freezing of the water inside. Since ice has a volume of about 110% of the water required to produce that ice, any freeze resistant pipe must either be strong enough to prevent the volume expansion or the pipe must be sufficiently expandable to accommodate the expansion. The availability of resilient plastic materials has provided hope of making a freeze resistant pipe, but until this invention such a pipe could not be made economically or commercially acceptable.
It is an object of this invention to provide an inexpensive freeze resistant plastic pipe. It is another object to provide a practical method for preparing such a pipe. Still other objects will become apparent from the more detailed description which follows.